Final answer:
The concentrations of hydronium [H3O+] and hydroxide [OH-] ions in aqueous solutions are inversely related through the equilibrium constant Kw = [H3O+][OH-] = 1.0 × 10⁻¹⁴ at 25 °C, meaning an increase in one results in the decrease of the other.
Step-by-step explanation:
In aqueous solutions, the concentrations of hydronium ions [H3O+] and hydroxide ions [OH-] are inversely related because of the autoionization of water, where water molecules dissociate into these ions. The ion product for water (Kw) indicates this relationship and is established as Kw = [H3O+][OH-] = 1.0 × 10⁻¹⁴ at 25 °C. This means when the concentration of hydronium ions increases, the concentration of hydroxide ions must decrease to maintain the equilibrium constant, and vice versa.For instance, if the hydronium ion concentration in an acidic solution is 2.0 x 10⁻⁶ M, the hydroxide ion concentration can be calculated by dividing Kw by the given [H3O+]. Therefore, [OH-] would be equal to 1.0 × 10⁻¹⁴ / (2.0 × 10⁻⁶) M, which simplifies to 5.0 × 10⁻¹ M. It's also worthwhile to note that pH and pOH values are related to these ion concentrations, reflecting the solution's acidic or basic nature.